REPRESENTATIVE SPECIES. 8r 



piper (T. macularius) of N. America, so closely 

 resembling it in winter plumage that no character 

 has yet been discovered by which it may be dis- 

 tinguished. Many other instances might be given 

 to illustrate this very interesting fact. 



If we look through the list of British birds 

 alone, we shall find that very few of them are 

 without representative forms or species in various 

 other parts of the world, and that in a very con- 

 siderable number these allies are exceptionally 

 numerous. In confirmation of the rule that the 

 wider the area of dispersal the more variable the 

 species, we may very aptly instance the Peregrine 

 Falcon (Falco peregninus). This bird may be 

 described as practically cosmopolitan, and breeds 

 from the Arctic regions southwards to the tropics 

 and the south temperate zones as far as Patagonia, 

 South Africa, and Australia. It may be very 

 easily imagined that the Peregrine has been and 

 continues to be subject to great differences of 

 climate and to many varied conditions of life 

 throughout such a vast area. The result has 

 been the establishment of many more or less 

 distinct representative forms or races, which pre- 

 serve a strong general resemblance to the typical 

 or parent species, whilst presenting minor differ- 



